[PATCH 8/9] cxl: Add DVSEC Register Locator

[Ben Widawsky <ben.widawsky@xxxxxxxxx>]

Signed-off-by: Ben Widawsky <ben.widawsky@xxxxxxxxx>
---
 lib/header.h |  8 ++++++++
 ls-ecaps.c   | 44 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 52 insertions(+)

diff --git a/lib/header.h b/lib/header.h
index 8141e13..b77a611 100644
--- a/lib/header.h
+++ b/lib/header.h
@@ -1120,6 +1120,14 @@
 #define PCI_CXL_PORT_ALT_BUS_BASE 0xe
 #define PCI_CXL_PORT_ALT_BUS_LIMIT 0xf
 
+/* PCIe CXL 2.0 Designated Vendor-Specific Capabilities for Register Locator */
+#define PCI_CXL_RL_BASE0_LO 0x0c
+#define PCI_CXL_RL_BASE0_HI 0x10
+#define PCI_CXL_RL_BASE1_LO 0x14
+#define PCI_CXL_RL_BASE1_HI 0x18
+#define PCI_CXL_RL_BASE2_LO 0x1c
+#define PCI_CXL_RL_BASE2_HI 0x20
+
 /* Access Control Services */
 #define PCI_ACS_CAP		0x04	/* ACS Capability Register */
 #define PCI_ACS_CAP_VALID	0x0001	/* ACS Source Validation */
diff --git a/ls-ecaps.c b/ls-ecaps.c
index b11d5a9..a0ef83d 100644
--- a/ls-ecaps.c
+++ b/ls-ecaps.c
@@ -800,9 +800,46 @@ dvsec_cxl_port(uint8_t* data, int rev)
   printf("\t\tAlternateBus: %02x-%02x\n", b1, b2);
 }
 
+static const char *id[] = {
+  "empty",
+  "component registers",
+  "BAR virtualization",
+  "CXL device registers"};
+
+static inline void
+dvsec_decode_block(uint32_t lo, uint32_t hi, char which)
+{
+  u64 base_hi = hi, base_lo;
+  u8 bir, block_id;
+
+  bir = BITS(lo, 0, 3);
+  block_id = BITS(lo, 8, 8);
+  base_lo = BITS(lo, 16, 16);
+
+  if (!block_id)
+    return;
+
+  printf("\t\tBlock%c\tBIR: bar%d\tID: %s\n", which, bir, id[block_id]);
+  printf("\t\t\tRegisterOffset: %016" PCI_U64_FMT_X "\n", (base_hi << 32ULL) | base_lo << 16);
+}
+
+static void
+dvsec_cxl_register_locator(uint8_t* data, int len, int rev)
+{
+  int i, j;
+
+  if (rev != 0)
+    return;
+
+  for (i = 0xc, j = 1; i < len; i += 8, j++) {
+    dvsec_decode_block(*(u32 *)(data + i), *(u32 *)(data + i + 4), j + 0x31);
+  }
+}
+
 static void
 cap_dvsec_cxl(struct device *d, int id, int where)
 {
+  u16 len;
   u8 rev;
 
   printf(": CXL\n");
@@ -824,6 +861,13 @@ cap_dvsec_cxl(struct device *d, int id, int where)
 
       dvsec_cxl_port(d->config + where, rev);
       break;
+    case 8:
+      len = BITS(get_conf_word(d, where + 0x6), 4, 12);
+      if (!config_fetch(d, where, len))
+        return;
+
+      dvsec_cxl_register_locator(d->config + where, len, rev);
+      break;
     default:
       break;
   }
-- 
2.31.1